Conveyer for supplying printing plates to presses



Dec. 9, 1952 w. GIBSON E1 AL CONVEYER FOR SUPPLYING PRINTING PLATES TOPRESSES Filed July 19, 1949 2 SHEETSSHEET l Dec. 9, 1952 w. GIBSON ET!AL CONVEYER FOR SUPPLLYING PRINTING PLATES TO PRESSES I 2 SHEETS-SHEET 2Filed July 19, 1949 Patented Dec. 9, 1952 CON VEYER FOR SUPPLYIN GPRINTING PLATES TO PRESSES William Gibson and George S. Bull, London,England, assignors of fifty per cent to Daily Mirror Newspapers Limited,London, England Application July 19, 1949, Serial No. 105,624 In GreatBritain July 23, 1948 8 Claims. 1

This invention relates to conveyors adapted more particularly for use insupplying stereo or other printing plates from a foundry to rotaryprinting presses.

The present method of conveying stereo plates from the foundry to themachine or press room of a printing office is either by means of aconveyor from the foundry to a central point of the machine room or bymeans of a conveyor which circulates round the machine room, operates oneach printing machine taking off the required plates by hand as theypass.

Conveyors of this type run at a low level and at a slow speed in orderto keep the safety factor high.

In a printing ofiice where the number of plates to be delivered torotary presses is large and the distance of travel is great, it isnecessary to deliver the plates to many stations at a high speed as theloss of time taken in delivering them from the foundry to the pressesmust be as little as possible.

To run separate conveyors from the foundry to each station would becostly and maintenance would be very high and impracticable owing to thelarge amount of space required.

The object of the invention is to provide a conveyor mechanism of thefree-roller type, arranged overhead in such manner that if the stereo orother printing :plates or the like bodies, which are in the form ofsegments of hollow cylinders, loaded on to it have been given asufficient velocity of motion at the commencement of their journey,gravity will maintain their speed until they reach their destinations.

According to the invention, the conveying mechanism comprises a bank ofconveyor rollers and one or more offtake chutes making junction with thebank of conveyor rollers and descending therefrom to the variousdelivery stations located along the conveyor. The bank of conveyorrollers is composed of alternate series of long and short rollers, thelong rollers being of a length sufficient to provide separatelaterally-overlapped paths of travel for the stereo printing plateswhich may be selectively placed upon the conveyor at its loading end instaggered out-of-line positions, depending upon the paths of travel theprinting plates are respectively intended to follow and the stations towhich they are to be delivered, each path of travel correspondingapproximately in width to that of a printing plate. The short rollersare located in the vicinity of the junction of the offtake chutes withthe bank of conveyor rollers, so that a printing plate may ride withoutinterference off the end of a series of long rollers onto an off-takechute leading downwardly at one side of the conveyor. The short rollersserve to support one edge of the succeeding printing plates intended fordelivery to stations located farther along the conveyor, and skids areprovided for supporting the opposite edges of such printing plates. Theskids bridge the space created by the oiftake chutes dipping away fromthe plane of the bank of conveyor rollers and these skids are suitablyprovided with gaps to allow the stereo printing plates to passdownwardly along the chute. For guiding the printing plates along theirrespective paths of travel, guide rails, suitably arranged in pairs forengaging opposite sides of a printing plate, are provided adjacent thebank of conveyor rollers and these guide rails desirably are extendeddown the chutes. Thus, the stereo printing plates fed onto the loadingend of the conveyor may be delivered to selected stations in accordancewith the transverse positions in which they are initially placed on theconveyor at the loading end.

The conveyor may include any suitable number of ofitak-e chutescorresponding to the number of delivery stations to be served. Aftereach series of short rollers, that is, following each 01T- take chute,the conveyor is stepped to a narrower width until at its discharge endit may be of a width corresponding to that of a single path of travelfor a stereo printing plate and may lead to the final delivery station.

The conveyor for the greater portion of its length may be slightlyinclined downwardly and the ofitake chutes may each comprise acontinuous series of secondary rollers extending downwardly from thebank of conveyor rollers at a steeper inclination than the conveyor.

The invention will be described in detail and by way of example withreference to the accompanying drawings in which:

Figure 1 is a view in elevation illustrating somewhat diagrammatically aconveyor arrangement for delivering printing plates to four stattions;

Figure 2 is a larger fragmentary view, in side elevation, of a portionof the conveyor;

Figure 3 is a plan View of a portion of the conveyor;

Figure 4 is an end view of the conveyor indicating the disposition ofthe printing plates thereon; and

Figure 5 is a detail View of the conveyor in transverse cross-sectionshowing the manner in which a printing plate engages a guide rail.

In Figure 1 of the drawings is diagrammatically illustrated the generalarrangement of a conveyor constructed in accordance with the inventionfor supplying segmental-shaped printing plates 4 to four differentdelivery stations.

The conveyor comprises a bank of conveying rollers arranged in series soas to constitute a generally horizontal portion I of the conveyor, andleading downwardly from the plane of the conveying rollers andterminating at the respective delivery stations are offtake chutes 2comprising separate series or banks of rollers 6.

The conveying rollers, as best shown in Figure 3, are arranged inalternate series of long rollers 3 and short rollers 5 with a series ofshort rollers 5 extending between the gap separating two adjacent seriesof long rollers 3. Each offtake chute 2 is inclined steeply downwardlyfrom a side of the conveyor at a location beyond the ends 50. of aseries of short rollers 5, so that a printing plate i riding down achute in the gap between the series of long rollers clears the ends ofthe short rollers, as indicated in Figure 3.

The long rollers 3 are of a width representing a plurality of laterallyoverlapped paths of travel of the printing plates, the width of the pathof travel of a printing plate corresponding approximately to the Widthof the printing plate, or the distance between its two roller-contactingedges. The length of the long rollers 3 (measured widthwise of theconveyor) of a series of long rollers following a series of shortrollers 5, considered in the direction of feed of the conveyor, issomewhat shorter than that of the series of long rollers preceding thesame series of short rollers. That is to say, the several series of longrollers 3 are progressively stepped back in length in the direction ofadvance of the conveyor. This follows from the fact that, since eachpath of travel of a printing plate along the conveyor terminates at anofitake chute 2, the combined overlapped paths of travel for theremaining printing plates intended for delivery to stations locatedfarther along the conveyor become progressively narrower beyond theseveral oiltake chutes, until the width of the rollers 3 leading to thechute 2a to the final delivery station corresponds approximately to thepath of travel of a single printing plate.

Similarly, the several series of short rollers 5 are progressivelystepped back in length to the same extent as the long rollers 3 tocorrespond to the narrowing width of the conveyor in the direction ofits length.

Extending lengthwise of the conveyor and along the ofitake chutes areguide rails 7 arranged in laterally overlapped or staggered pairs, witheach pair of guide rails defining a path of travel for a printing plate.These guide rails are supported on transverse structural members 8 andare so positioned that diametrically opposite edges of the plates areengaged by the rails to retain them in their laterally ofiset orstaggered relationship and to insure that the plates will be deliveredto their proper stations.

Bridging the gaps between successive series of long rollers 3 areparallel-arranged skid plates 9, the construction and arrangement beingsuch that those printing plates traveling to more distant stations alongthe conveyor will have one of their edges supported on the short rollers5 and the other of their edges supported on one of the skid plates 9.

In order to allow a printing plate 4 to roll down one of the chutes 2 toa delivery station without obstruction, the skid plates are interruptedintermediate their lengths to provide a small gap or clearance W to passthe printing plate therebetween.

In the operation of the conveyor just described, the stereo printingplates are loaded onto the conveyor at its receiving end and are guidedalon their respective paths of travel by the guide rails 7. Dependingupon the position laterally of the conveyor in which the printing platesare loaded onto the conveyor, the printing plates will be selectivelyguided to the desired delivery stations. The printing plates will travelalong the conveyor rollers guided by the guide rails 9 and pass over thegaps between successive series of long rollers 3 with one edge of theplate supported on the short rollers 5 and its other edge supported on askid plate 9, both short rollers and skid plate being located in theplane of the conveyor. When the printing plate nears the deliverystation to which it has been consigned, both edges of the printing platewill pass off onto the rollers 6 constituting the oiftake chute 2 and,owing to the steep inclination of this chute, will be impelled bygravity to the delivery station.

The width of the conveyor becomes progressively narrower in stagesbetween succeeding offtake chutes so that ultimately the long rollers 3narrow down to approximately the width of the path of travel of a singleprinting plate. Thus, a printing plate destined for delivery at thefinal station rolls off the steeply inclined conveyor rollersconstituting the ofitake chute Ed at the terminal end of the conveyor.

By virtue of this construction the printing plates may be convenientlyand speedily delivered from the foundry to any selected one of aplurality of stations located at various locations in the printingmachine plant.

The conveyor may be of the free-roller type or partly of the free-rollertype, but provision may be made for driving all or certain of therollers to effect the conveying operation. Provision may also be madefor braking certain of the rollers and particularly those which formrelatively steeply inclined parts of the conveyor system.

While the invention has been particularly described with reference tothe conveying of printing plates, it is equally adapted for use in thesupplying of other objects in the form of segments of hollow cylindersand the like.

We claim:

1. A conveyor for delivering segmental-shaped articles such as stereoprinting plates to stations located at different distances along theconveyor, said conveyor comprising a continuous bank or"article-supporting conveyor rollers consisting of alternately occurringseries of long and short rollers, the long rollers being of a lengthcorresponding to the width of a plurality of laterallyoverlapped pathsof travel for the articles arranged in successive, out-of-line positionson the conveyor, a plurality of ofitake chutes leading to deliverystations located at various distances along the conveyor, said oiftakechutes each making junction with an end of a series of long rollers andinclined downwardly at one side of the conveyor to a delivery station,said chute being disposed clear and beyond the ends of the adjacentseries of short rollers, skid members extending in the plane of the bankof conveyor rollers and overlying the chute for bridging the spacebetween alternate series of long rollers in such manner that the skidsand short rollers provide support for opposite sides of onwardlytraveling articles intended for delivery to more distantly locatedstations, said skid members being provided with gaps to afford passagefor the articles moving downwardly along the chute, and guide meansextending along and adjacent the bank of rollers adapted to engage anddirect the articles along their respective paths of travel.

2. A conveyor as set forth in claim 1 wherein the bank of conveyorrollers extends downwardly at an inclination from the loading end of theconveyor towards its discharge end for the gravitational travel of thearticles therealong.

3. A conveyor as set forth in claim 1 wherein the oiftake chutecomprises a series of rollers arranged at a relatively steep angle tothe horizontal.

4. A conveyor as set forth in claim 1 wherein the guide members comprisepairs of complemental rails extending along and above the bank ofconveyor rollers and defining the laterallyoverlapped paths of travelfor the articles.

5. A conveyor as set forth in claim 1 wherein the length of the rollerscomprising a series of long rollers following a series of short rollersconsidered in the direction of feed of the conveyor is less than thelength of the rollers comprising the series of long rollers precedingsaid series of short rollers.

6. A conveyor as set forth in claim 1 wherein the lengths of the rollerscomprising the series of both long and short rollers following anofftake chute considered in the direction of feed of the conveyor areless than the lengths of the rollers comprising the series of long andshort rollers preceding said ofitake chute.

'7. A conveyor as set forth in claim 1 wherein the approximate width ofthe ofitake chute corresponds to the difference in length between theshort rollers and the long rollers located immediately in advance of thechute.

8. A conveyor as set forth in claim 1 wherein the length of the rollerscomprising the final series of long rollers in the bank of conveyorrollers corresponds approximately to the width of a single path oftravel for an article and terminates at a final delivery station.

WILLIAM GIBSON. GEO. S. BULL.

No references cited.

